also depends on whether you are going low crowd season or not.
Last yr, for my end of Jan trip, I made ressies in Oct/Nov and into Jan for lots of places, including Rose & Crown (for Illum), Le Cellier (ended up with 2 ressies), Ohana (a perfect 5pm ressie), HDDR, Chef Mickey. we had 10 days of TS meals to book.
The only ones that were slightly difficult were:
Ohana - tried to get a 2nd ressie and had absolutely no luck. Kept trying daily after we got there too.
Le Cellier: got a 2ish/3ish ressie so not my first choice. Finally in jan after haunting various cancel ADR threads, I got a dinnertime ressie. We kept both ressies for the trip (it was awesome).
HDDR: Friends we met up with at WDW decided on the day of that they would like to join us at HDDR that night. We called all afternoon. They kept saying no. When we got there to check in, we asked yet again and amazingly enough - the answer was YES! We were shocked. (sadly, they were in the middle of IASW and couldn't make it over in time to join us).
Our upcoming trip is end of Aug. I was trying to book at 180+10 (in Feb), but due to various things, my TA booked a few days later. Had no trouble with our ressies. A few weeks ago, I saw a thread raving abt the new menu at CRT bfast. So I added that around end of April/early May. That's 4 months out. No problems getting the exact time I wanted and I would expect bfast to be the most popular meal?
Keep in mind - all this is during
free dining.